What should be downloaded to use Qt?
Nothing is clear in this site. Much of texts without any usefulness. For example if to select "How can you get started" a screen with description of Qt 4.8 Release candidate is displayed. If to select "Downloads" a screen with Qt SDK with Qt library 4.7.4 is displayed. What is online installation (15 Mb) ? What is offline installation ( 1.6Gb)? What is Windows-MinGW (356Mb)? What is Windows-VS2010 (273 Mb)? Nothing is clear. It looks like inadequate persons filled the contents of the site.
Can anybody to explain step by step what should be downloaded for Windows environment? Of course I do not want the Release candidate 4.8 because I am bot doubt that it is full of bugs.
Judging from the content of you post you are in need of some programming 101 before you proceed.
Online installation means you only download a small installer and it installs Qt from the internet. I do not recommend this unless you are low in disk space. Just download and install the offline installation. It contains everything you will need to use Qt, but I doubt you will be able to do that right away if you have such a hard time already and don't know basic stuff like what MinGW or VS2010 stand for. Everything is pretty much clear with Qt, the library has extensive and awesome documentation and more examples than any other comparable library.
You are bot doubt? Well, you almost sound like a bot ;) Qt 4.8 is quite healthy, it is way past beta stage.
Judging by your name you should really go into the Bulgarian sub-forum here and ask your questions in your native language, perhaps it will make more sense to you. If you really have the impression the site is maintained by "inadequate" "persons" that is probably due to your poor English, to me the content of the site makes perfect sense, and I think I speak for the vast majority of people here.
Thanks for your replay.
Of course I know what is MS VC 2010 and MinGw. I wonder why the sizes of downloads are so different. I thought that I can load a Qt library and use it with any Windows C++ compiler after running an appropriate project build for the library.
It is very confusing that if you are selecting different paths of download you are suggested different sets of tools. I do not understand why for novices are suggested to download the Release candidate instead of stable release.
The site looks like a reclame of Herbalife: much texts and little usefulness. For example the section "How can you get started" shall start from instructions how to download the tools.
In any case the first expression is very negative.
As the name implies, "RC" is a Release Candidate - so, in theory, it's as good as stable. Qt 4.8 is being tested for a few months now and is stable. I've been using it for months without any problems. So what's so bad about advocating that to people, even if they are new to Qt?
bq. For example the section “How can you get started” shall start from instructions how to download the tools.
Well, it points to a download location with clear links. I imagine that a person willing to use a framework has enough knowledge to know, that clicking on a link in "downloads" section will - surprise! - start downloading a file? Also, all files are clearly described.
The fact that surprised me right now, and here you are right, is that the link on main side advocates Qt SDK, but upon clicking, links to just the libraries show up, with no mention of SDK. That should be fixed. For any rookies, I would recommend the SDK. For experienced users too, but they know that themselves :)
Those two (Windows-MinGW (356Mb), Windows-VS2010 (273 Mb)) are pre-built for use with either the GCC or the MS VS2010 compilers. Naturally, you can also download the library source code and compile it yourself, but from personal experience - that is a slow and lengthy process that may very well take up to a few hours. What other compiler would you want to use on Windows besides GCC or the MSVS one? As I word of caution - I have tried to compile the 4.7.2 library with the Intel compiler a few months back, but it is a NO GO, there is an still unresolved bug that is supposed to be fixed in version 4.8. That being said - the Intel compiler is able to build Qt applications using the Qt library, compiled with VS, I haven't stumbled upon any issues, although I have only done basic core and gui stuff.
The difference in size is simple - Qt is designed to make use of platform native resources, that is why the MS compiler version is significantly smaller, since MS have already provided plenty of code which Qt uses when coupled with the MS compiler. Despite the size, those two offer the same functionality, based on the Qt library, there is nothing missing or incomplete if that is your concern.
I don't think it is a feature that the "getting started" link sends you to prereleases - it is probably a bug, but the page clearly states that those are "Current Qt Technology Previews, Betas and Release Candidates" - as I said, the RC4.8 is actually quite healthy, I have used its prebuilt for Visual Studio 2010 without bumping into dead ends. That being said, the recommended thing to do is to simply go to the "download" page, which contains final versions, and either get the full package, or the online installer and specify what components you want installed. If you own Visual Studio and plan to use it - get the VS addon. Visual C++ Express in not supported. Qt Creator is pretty darn sweet for a free software product, sure, it lacks advanced features like performance profiling built in, but it integrates nicely with the library and has better auto-complete than the stock one available for VS and a nifty set of editing features, like inserting definitions from declarations, syncing changes in those and many other time saving tricks which I suggest you get into.
On a side note: Qt 4.8 just got final :
Thanks for your advices. I have installed SDK for Windows (as I think) and started Qt Creator. But now I can not find the Wellcome page! Looking throw the "Getting Started" I see a different image of Qt Creator. My Qt Creator contains only two push buttons "Getting Started" (in Russian) and "Develop" but I do not see "Demos and Examples" as in the picture in the documentation. So I can not execute the first step of "Getting Started" because there is no "Demos and Examples" on the first screen of Qt Creator. So are there the demos and examples in Qt Creator?
Also it is not clear after installing SDK what else I should install or to do because I do not see any reference to a C++ compiler.
Ctrl+1 gets you to the Welcome screen, in the top you have three tabs - Getting Started, Develop, Demos and Examples - this is for the new Qt Creator 2.4
If you have the "old" 2.3 version, look for a checkbox in the bottom "show demos and examples" or something like that.
The Qt SDK comes with gcc 4.4 integrated, you just write your code and hit the Build icon (a hammer) in the bottom left of the Creator window, then hit the Run icon (a green triangle arrow) and it's on.
I have to agree with the OP, not so much on specific details, but the overall flavor. The site and Qt Creator are visually very appealing but the documents are written as reminders to people who already know how to do this. There are huge assumptions of knowledge and steps left out. Also, the documentation does not seem to apply to the current revision and/or platform. Examples:
I did an online install of the SDK on Mac OS X 10.6.8. I accepted all defaults during the install, which placed the files in /users/bananas/QtSDK
Starting QtCreator I see getting started documentation. It tells me, "On the Welcome page, select Demos and Examples, and then search for Toys: Clocks Example in the list of examples."
That example is not installed.
Well, this thing is big but can I just go into terminal and do a command line compile?
I see some command line demos on the web site here, for example: http://doc.qt.nokia.com/4.7/gettingstartedqt.html
Perfect. Type 12 lines and a make command. Oops.
-bash: qmake: command not found
A search shows 4 instances of qmake.
Well, are they the same? Which one should I add to my path?
I do a little googling and see that the usual path is /usr/local/Trolltech/Qt4.7/bin
Oh, but that isn't where the (default) install put it.
So, here's the point. There are thousands, possibly millions of man-hours in this thing. It's visually appealing. But you are building a huge wall between this SDK and many more potential developers. If your focus is to create programmers in college level classes with lectures and recitation sessions with TA's OK. If you want any hobbyists to join in, you're out of luck. Learning curve is too steep.
I should be able to grab the application bundle, drop it into my applications folder and there it is. "Install" shouldn't happen.
I see the installation log is 1.5MB ?!?
The name of my application should be allowed to have whitespace in it. Qt Creator has a space in it!
Simulator? Simulate what?
All great options, but too much to see on day 1.
I should be able to start Qt Creator and type in "Hello World" and have it run.
Go ahead, tell me I need programming 101 like you did the OP.
Snarky remarks about programming 101 are not helpful. I had programming 101 exactly 25 years ago this fall. I wrote applications in the 90's for Mac OS7,8,9 but since then (most of the 2000's) I have been working on microcontrollers. How much functionality can you fit in 16K or ROM and 4K of RAM?
We live in different universes.
Why am I here? Simple: I'm looking for a cross platform solution to put a UI on a PC/Mac/Linux box, possibly a hand held device too, that can talk to the microcontroller over the LAN and/or bluetooth. And I'm rather sick of the ugly (UI) Java fecal matter that has been available to do this up until now.
If you don't know what I mean, grab yourself a copy of the Arduino development system. Any platform. Equally ugly.
If you expect to move with absolute confidence just a few minutes after taking a look into a new framework, then you should expect similar problems in any framework you pick (a good illustration: boost).
Otherwise, the points you raise are valid, and it's good to have some fresh look on things. Docs are, obviously, being written by people who already know how to move around in Qt. Nokians and people in Qt Project are usually happy to get new bug reports, so you can point out those issues on mailing list, or JIRA (links available on qt-project.org) - and thus help any future newcomers :) I proposed a wekk or so ago to create a group of people who would update the documentation based on user input on DevNet, but this proposal did not yet meet with much response.
A thing to remember (or know), though, is that SDK is not exactly part of Qt itself. It is just a handy wrapper to ease installation process - that is why it is not included in docs. Yeah, it sounds and is weird, but that's just how it turned out to be - due to historical reasons. Qt is still being most thoroughly tested and fitted for a manual build of the source code (especially when we talk about embedded devices). Additionally, Qt is now being moved into a separate - free and openly governed - environment, Qt Project. If you want to use examples in SDK, they have to be specifically turned on in SDK maintenance tool (or during installation). They reside in Miscellaneous menu. I don't know whether they are 'on' by default, it's been a few years since I've last run any example.
The getting started guide is aimed at people using terminal - you don't have to run these commands in Qt Creator, IDE will do this for you. Simulator is used to simulate deployment on a mobile device (Symbian, MeeGo + Android if you have Necessitas installed). QMake you want to use is the last one - described as "desktop".
That's it for now, hope it helps at least a bit. If you have further problems - please ask.